Metal casting system



Sept. 25, 1956 F. NIELSEN 2,763,905

METAL CASTING SYSTEM Filed Sept. 20. 1954 IN VENTOR Ci TToRNEa/s UnitdStates Patent (3 METAL CASTING SYSTEM Friedrich Nielsen, Muhlacker,Germany Application September 20, 1954, Serial No. 457,148

6 Claims. (Cl. 22-434) This invention is directed to a process andapparatus for the casting of metals.

This invention is an improvement on the casting process and apparatusdisclosed in my co-pending application entitled Casting Metals, filedJanuary 9, 1953, Serial No. 330,479, now Patent No. 2,735,147, issuedFebruary 21, 1956. In said application I disclosed a runner system inwhich the energy of the flowing metal in a covered channel a number ofabrupt turns. e

The objects of the instant invention are to produce a method and arunner system in which the metal is led through uncovered, or open,channels in such a way that the energy is dissipated and the metal ledinto a mold in a non-turbulent, non-foaming condition.

In general, the objects are accomplished by causing the molten metal toflow through a series of open channels of successively increasing size,and having means for causing the metal to lose energy in the channels.The end or outlet channel can extend perpendicularly or substantiallyso, and is connected to the conventional gates on a mold which extendsover substantially the entire height thereof. The first or inlet channelsection can receive metal from a preliminary runner extending in thegeneral direction of the channel sections. Such runners can be filledfrom below through a deflected inlet or through any other known means.They can also be connected to vari ous points of the channel system inthe manner disclosed in my aforesaid application, Serial No. 330,479.The runners can be filled from above or connected in the form ofdownwardly extending branches as again shown in said application, SerialNo. 330,479. Finally, the preliminary runners can be formed as inletrunners constructed according to the general formula:

could be dissipated by causing the metal to flow around mXV in which Iis the runner cross-sectional area, h is the distance of fall of themetal, V is a value which equals, or is proportional to, the volume ofmolten metal flowing through the system per second, m is a coeflicientbetween 1 and 5, n is for an exponent between 0.5 and 1.5. Again thesespecial inlet channels can be filled either directly from above, as froma hopper or an adjacent gate system.

The open channels can merge into a reinforced riser which extends in thegeneral direction of the open channel sections, and the riser is thenconnected to the individual gates or a single gate, leading into themold, and then functions as a riser in the solidifying of the metal.

The means by which the objects ofthe invention are obtained is describedmore fully with respect to the accompanying drawings, in which:

Figure 1 is a perspective view of a plurality of open channel sectionsaccording to the invention, and

Figures 2 and 3 are perspective views of modifications of the invention.

In Figure 1 a plurality of channel sections 2, 4, 6, 8

and 10, are connected at angles to each other. The metal flowing throughthese channel sections from the'inlet:

. In Figure 1, 60 angles have been shown. The suc-' cessive channelsections are widened at a ratio of about 1.20 to 1.28. The metal flowssubstantially horizontally through the sections. Depending upon theratio applied to the widening of the channel sections, the top surfaceof the flowing metal inclines more or less downwardly from section 2 tosection 10, and also within each of the channel sections.

The metal flows from a head in runner 12, correspond-' ing to the levelof the metal to be cast in the mold. It flows successively throughsections 2 to 10 with a constantly decreasing velocity, and withoutturbulence, splashing, or foaming. In Figure 1 channel section 10 canfunction as a direct gate to the mold, which in this case has thickwalls.

Figure 2 is a perspective view of a modified channel system. From thepreliminary runner 14 extend channel sections 16, 18, 20, 22 and 24, insuccession. The channel sections are not connected at angles to eachother as in,

Figure l, but angled walls are included in the system, and serve todissipate the energy of the flowing metals, but maintaining thehorizontal flow of metal. In channel section 18 the walls are bent intoangles which serve as corners to interfere with the flow of metal andthus reduce the velocity of flow. The cross-sectional area of channelsection 18 is increased over that of section 16, while thecross-sectional area of the next section 20 is decreased from that ofchannel section 18, although it is increased over that of channelsection 16. Thus, from channel section 16 through section 20 thecross-sectional area is first increased in section 18 and thenrestricted in section 20 of a short distance. Similarly, the nextsection 22 is increased, and then decreased in section 24. The width ofsections 16, 20 and 24, is continuously enlarged, thus taking intoaccount the desired slowing down of the velocity of flow. The loss ofenergy occurs by reason of the narrow walls, or at the corners betweenthe alternately spaced angled wall sections. There is also a loss ofenergy due to local turbulence, which occurs without foaming, and also afurther loss of energy as the metal flows in two branches from thecorners of sections 18 and 20, which branches merge before entering thenext narrow section. The amount of loss of energy is determined by theratio of enlargement of each of the restricted channel sections. Noexact mathematical and physical formula can be given for it becausethere are a plurality of interconnecting causes. However, the total lossof energy can be empirically decided. v

The system of Figure 2 can be modified by increasing the area of thechannel sections in an upwardly directed conical manner. Suchenlargements must not apply likewise to both the channel sections 16, 20and 24, and the intermediate sections 18 and 22. The general purpose ofthe upwardly directed enlargements, either in the form of cones orsteps, is to reduce the total resistance of flow in the upper portion ofthe channel sections in order to force the hotter metal flowing in fromrunner 12 to the top of the casting in the mold. This effect can also beachieved or increased by omitting either gradually or abruptly one ofthe channel sections. If simple castings are to be made in which nospecial quality is sought, it is sufiicient to use a system having buttwo small short channel sections and one intermediate section, such asthe use of sections 16, 18 and 20, alone.

In Figure 3 the channel section is somewhat similar to Patented Sept.25, 1956.

Figure 2, but isasymmetrical. The preliminary runner 261s filled fromabove. The metal flows through channel sections 28, 30, 32, 34 and; 36,into a riser 38. This e is onn cte th. t e ndi d al sate .Q., .a. t gto,hev mold: Th f ects. t r duc he veloc ty it-the molte m l; e. ach e jinF ur 2. bvrmea isaof e ng ed. l s t e t o 0 a d 3 hich are c n e ted'fh. in e med ate ons r cted ct o A a e. sy t m ash r i r bed. a d. alson om ne o h. h sy t di l my app ca on S ial No. 330,479, has adva tagesboth in molding and casting echniques. F r. ez amp' et v comp i at dCast n s o e.

m d. o o elp ane Qan'be i ted; Su P cu arly happ ns when the bo tom. p to -c tingsan h'emadeby s mple. rdi ary Rout ne; Her h fi owe t Pa t ofthe mold. avity a e rea hed t rough he 09 1 y he n hann l sys em tho t iot ins,v p te ofthe lling.

fl'ow of' metal. Also in the permanent mold casting of Piece ha n p r cuar yn. a e t i n 0r ep rating plane of which stands perpendicular, thedisclosed channel systemis very successfully used. On the other hand, inthe casting of pieces having extremely thick Walls, the disclosedchannel system can cast the metals at lower speeds than have heretoforebeen used.

Having now described the means by which theobjects of the invention areobtained, I claim:

'1. A casting system for leading metal into, the gates of a moldcomprising a plurality of open channelsections of. substantiallyeven'height connected together to a channel system, each channel sectionfromthe inlet end to the outlet end of said system being increased incrosssectional area with respect to aprior sectionjfor reducing thevelocity of the metal flowing through the channel system, and anglemeans for the channel sections for further reducing'the metalflowvelocity.

2. A system as in claim I further comprising channel sections ofrectangular cross-section and having a height greater than their length,and said channel sections being connected to each other at anglesranging from 20 to 3. A system as in claim 1, further comprising channelsections alternately enlarged and constricted sections with like-shapedsections being progressively enlarged toward the outlet end of thechannel system.

4. A systemasin claim. 3, further cgrnprising angled walls for theenlarged channel sections.

5. A system as;in.claim 1, furthencomprising a vertical preliminaryrunner connected to the inlet end of said channel system, said runnerbeing open at the top and having a downwardly decreasing cross-sectionalarea.

6. A system as in claim 1 further. comprisinga'preliminary inlet runnerfor said channel sections .construgted aceording to the formula:

wherein fis the runner cross-sectional area, 11 iswthe distance offalloi the metal, V;is a value-equatorpro.- nortien q e vo ume-0 meta fl w oh the' y tem per second, In is a coeflicient between land 5, and n isforanexponent between 0.5;and 1.5.

References Cited inthe file of this patent FOREIGN PATENTS 617,959Germany Aug. 30, 1935

